Why Does My Bathtub Turn Black?

Why Does My Bathtub Turn Black?

Many people complain that their bathtubs turn black after using them for a few months. However, it is easy to fix this problem by adequately maintaining your tub.

Why Does My Bathtub Turn Black? Your bathtub can turn black due to the growth of microscopic black mold and the use of hard water. In addition, tannins and dissolved magnesium cause dark rust spots inside the tub. Damaged carbon filters and open windows can also cause this problem inside their walls.

Notice the issue and try to find out its root causes. You can also call an expert to fix these problems.

Growth of Black mold

A common cause of black bathtubs is the growth of black mold. Sometimes you notice it is turning dark, but it is not the dirt. You become confused because they look blurry, and you cannot see them. 

However, black mold grows in the shower curtains and expands to the tub surface. 

They can also grow when the water in this tub does not dry properly.

You can use cleaners that specifically clean this mold. They work best on their surface because of their non-porous material. 

You can use a standard-size bottle of antifungal spray to clean the tub and apply it thoroughly over the surface. Then, wait for 5 to 10 minutes, scrub the affected portions with a non-scratchy brush and wash with water. 

Dissolved iron

Rusty drainage pipelines are also responsible for the darkening of your bathtub. Plumbing material gets rusty, and you notice dark rust spots on your tub.

Iron particles enter the water and immediately dissolve in it. However, they get oxidized when exposed to oxygen and convert into iron oxide. 

This chemical reaction results in the corrosion of several colors. 

It is essential to describe that you should not use bleach on these dark spots because it can worsen the problem. The water in this tub will turn black when magnesium in your water supply interacts with it in steel pipelines. 

It causes dark specs inside the tub around its walls, which further darkens if left untreated. This also makes a bathtub dirty. An easy method to clean these stains is to use a mixture of two good quality cleaners. You can use two standard-size spray bottles and apply one coat of the first cleaner. 

Let it dry, apply a thick coat of the other cleaner on its surface and mix it thoroughly. Wait for its complete drying and wash it with cold water. It is an effective method for washing out these stubborn rings.

Worn-out Carbon filter

Hydrogen sulfide is a chemical that produces the worst odor. However, there are several methods to remove these chemicals from water. One of them is the use of a carbon filter. 

They make the water odorless and tasteless by removing these inorganic chemicals. In addition, it indicates that your carbon filter is out of order when you see black specs in the bathtub. 

The faulty bathroom exhaust is also a reason to darken it due to its poor function. The remaining water in this tub does not dry completely if the exhaust is out of order. 

The minerals dissolve in this water and create a dark look that is unpleasant to see. It is an alarming sign to replace the carbon filter to ensure a clean water supply. 

Open windows in the bathroom

Your bathtub can turn black when your bathroom windows are open for a long time. This is because the dust and soil particles easily enter the bathroom and stick around its walls. 

The location of the tub plays a significant role in turning it dark. Sometimes your pets bring soil particles along their paws which accumulate in the tub. 

They can directly get the sunlight when the tub mounts in front of a window in the bathroom. 

These particles get wet with water and allow the penetration of sunlight in them. It will eventually give it an ugly look. You should wash the tub thoroughly once a week or at least fortnightly. 

Tannins in water

Tannins are organic materials that are soluble in water. They are a significant culprit in turning your bathtub dark and yellowish. This is because they mix with water when it passes over the decaying flowers or leaves.

 They turn the water dark yellow which darkens the walls of your tub. In addition, they produce an unpleasant odor in the water, which smells like a musty odor. 

You can use chlorine rather than bleach to remove tannins from the water because bleach makes these stains permanent.

 Use a water softener before using any tannins removal system. The reason is that they help to convert the hard water into soft water, which minimizes the tannin content.

 You can effectively use ultrafiltration to clean water from impurities like tannins.

This system consists of a membrane that pushes the tannins with slight pressure and cleans the water. Call a professional to fix it when you cannot do it without professional assistance. 

Use of Hard water in the bathtub

It is a kind of water that contains several dissolved particles. These are mainly magnesium and calcium, which you feel as residues on your body when you bathe in hard water. 

These residues stick together and make a curd-like texture which causes dark rings in the tub. It does not let the soap clean the bathtub and your body.

 Take a small bowl, fill it with white vinegar and clean these spots. 

Arrange a few paper towels, dip into the bowl and directly apply them to these spots. 

Wait about 45 to 90 minutes to let it work, and gently scrub it with a mixture of baking soda and vinegar. Then, rinse the tub with lukewarm water and let it dry naturally for some time.

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